Centrifugal pump lubrication of rolling bearings mainly is to reduce friction power consumption, lower wear rate and also act as a cooling, dust, rust and vibration absorbing effect. Good lubrication is to ensure that equipment normal operation, reduce equipment wear and tear, prevent accidents, reduce the power consumption, prolonging the service life of the repair cycle and effective measures.

Baking furnace circulating water system by use of centrifugal pump is single stage single suction pump, all kinds of technical parameters are as follows:

Models for IS150-125-125, flow rate of 200 m3 / h, 20 m, lift shaft power 18.5 kw, the speed of 1450 r/min.

This type of number of water pump bearing lubrication is by 30 # (winter) or 40 # (summer) mechanical lubricating oil. Due to design dynamic seal leakage is very serious, not only causing huge waste of oil, bearing damage, and pollute the environment, is not conducive to the safe running of the equipment and the civilization production. In the years of work, in order to solve this problem, many times to bend small leather.

1, lubrication mode transformation process

1.1 the felt seal instead of single skeleton oil seal

The original bearing box sealing is sealed with a mantle. Leakage is very serious, each pump fuel consumption is about 300 kg/a, cause a large amount of waste oil, a thick layer of oil on the ground.

In order to change this kind of oil spill, felt for the skeleton, as follows:

(1) inside and outside the end cover of bearing box processing, car out a Φ 65 mm, 12 mm deep hole, put a specification for 45 mm x 60 mm x 12 mm of skeleton oil seal.

(2) take off will be felt, the skeleton oil seal with a hammer in gently, and installed correctly.

After renovation, equipment operating normally, vibration displacement is about 0.04 mm, the bearing outer temperature of 50 ℃ or so, each pump in oil consumption only 50 kg. Keep the pump room clean sanitation, to eliminate the due to lack of oil bearing, shaft damage accidents, make the equipment running in good condition.

1.2 single skeleton oil seal is changed to double the skeleton oil seal

In order to reduce leakage more, according to the structure of bearing box cover, and put forward the reform plan, the bearing box end cover inner hole machining for Φ 65 mm hole. The single skeleton oil seal is changed to double the skeleton oil seal:

Trial operation shows that this method is very effective in the short term to prevent leakage. But after 6 months of continuous running, will increase the leakage due to skeleton oil seal wear.

2, the defects of skeleton oil seal

Change the felt seal to skeleton oil seal, with 4 a, although the effect is good, but it has obvious flaws.

In practice, because of short life skeleton oil seal, often need to change, change in skeleton oil seal, need to disintegration of all equipment, on the one hand, increase the labor intensity of workers, on the other hand, in the process of equipment overhaul the sometimes causes the damage of impeller, the bearing parts, do not conform to the requirements of the equipment of economic management, but if we don't change oil seal, cause leakage, is not conducive to seal, also directly affect the bearing life. All in all, the practice proved: skeleton oil seal not completely solve the structure of bearing box leak.

3 instead of lubricating oil and grease

Currently, cheap and without leakage of sealing device: no, not yet. Some sealing effect is good, but the price is expensive, not economically feasible. After investigation and study, decided to use bold experiment instead of lubricating oil to lubricating grease.

3.1 transform method

Considering the pump shaft power is 18.5 kw, traffic is 200 m3 / h. Pump speed of 1450 r/min, linear velocity of 3.4 m/s. From the above two points, grease lubrication is feasible.

3.2 specific methods are as follows

(1) put the oil within the tank, to clean bearing box.

(2) the end cover at the ends of the bearing box and the oil drain plug is opened, to eliminate the casing air.

(3) the lithium base grease with butter gun by lubrication to the bearing box injectors, added to the grease from the two end cover and oil drain hole extrusion, as fill, and tighten the bearing end cover and the oil drain plug. Turning with the hand, make the grease evenly distributed over the casing.

After start the pump, open outlet valve, make the pump running in normal case, monitoring on both ends of the bearing temperature and oil pump. Using infrared thermometer monitoring temperature, after the modification of vibration displacement is about 0.04 mm.

Grease oil is good, no change, pump operating normally, can be seen from the temperature monitoring data and vibration monitoring data, grease instead of lubricating oil is feasible, can be used widely in the same type pump.

3.3 grease lubrication effect

The grease is not easy to leak, be helpful for the water pump bearing lubrication, to ensure the safe and stable operation of pump, greatly reduce the amount and the number of refueling. Not only fuel, and reduce the labor intensity of workers. Specifically:

1) save oil costs. Use of lubrication oil pump consumption of 9 kg/each a, cost is RMB 63 / a. And oil consumption in the case of skeleton oil seal intact 4 kg/month, cost is RMB 200 / a. Each pump can save 137 yuan/a, greatly reduces the cost of lubrication.

(2) reduce the maintenance cost. Skeleton oil seal life expectancy for four months, to replace the skeleton oil seal, the need to overhaul the 3 times a year or so, pressure blasting machines, instead of lithium base grease, reduce artificial cost. Cost of raw materials, machinery, and to avoid the equipment parts damage caused in the process of maintenance.

(3) to extend the equipment operation cycle. From the aspects such as vibration, temperature monitoring, the use of grease sealing performance is good, bearing a well-functioning, prolong the service life of bearing.

(4) to improve the job environment.

4, endnotes

Anyhow, grease instead of mechanical lubricating oil, the speed is low, the small flow of pump is feasible, and has obvious economic benefits and environmental benefits, the device is an effective measure of economic reasonable operation.